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So I'm installing a new MHI turbo in my X and when I removed the exhaust manifold I found a small crack on the inside of the collector between the runners. How dicked is it?
I'd really like to get my car back together, the MAP cast exhaust manifold is back ordered for weeks and tubular headers are both significantly more expensive and not what I want on my daily driver.
Am I risking much by just continuing to use the cracked manifold until I can get it replaced properly later this summer?
This isn't my header but this is an extremely similar crack:
So, worth risking it or do I pull out the stops to get a replacement? (likely tubular)
Last edited by KVandy15; Feb 29, 2016 at 09:47 AM.
So I'm installing a new MHI turbo in my X and when I removed the exhaust manifold I found a small crack on the inside of the collector between the runners. How dicked is it?
I'd really like to get my car back together, the MAP cast exhaust manifold is back ordered for weeks and tubular headers are both significantly more expensive and not what I want on my daily driver.
Am I risking much by just continuing to use the cracked manifold until I can get it replaced properly later this summer?
This isn't my header but this is an extremely similar crack:
So, worth risking it or do I pull out the stops to get a replacement? (likely tubular)
Hold off for the MAP cast manifold, I have it and it's a great piece. Just install a set of bolts in place of the two back studs so changing the manifold is a piece of cake. That's what I did. But yeah that crack will only get worse over time
Should be useable until you get the MAP piece if that's what you really want. Most of the X manifolds crack at some point while on the car and people don't know unless they take it off.
So I lied, I couldn't bring myself to install the cracked manifold and I didn't want to wait weeks to get an investment cast manifold so say hello to my new friend...
Oh I know, but it's not already cracked so big improvement from where I was. The part also comes with a lifetime warranty so when it does I'll have some recourse.
Homebrewed, I took some queues from the shield map includes in the T3 hotparts kit but that one leaves some small parts of the valve cover exposed and is designed to be used with an aluminum valve cover. I needed a more robust solution for the plastic valve cover so I rolled my own.
How long a tubular lasts is totally hit or miss and also dependant on the MFG. For track use, i wouldn't use MAP tubular mani. For street use, its as good as anything else that doesn't come with a lifetime warranty. It's hard to beat full race simply due to their lifetime warranty. A handfull of other companies offer warranties as well with their tubular mani's.... but FR has been doing it for like 20 years, so they've got this whole production tubular manifold thing down to a science.
FWIW, cracks in your stock manifold are fine. They might leak when the manifold is cold, but as soon as it heats up the cracks seal. I have cracks in mine and i track the **** out of it. No evidence of exhaust leaks from the mani just from inspecting the inside of the heat shield. Usually a leak will show up as carbon deposits on the shield or it'll straight burn through if the leak is bad enough. The inside of my shield is clean.
How long a tubular lasts is totally hit or miss and also dependant on the MFG. For track use, i wouldn't use MAP tubular mani. For street use, its as good as anything else that doesn't come with a lifetime warranty. It's hard to beat full race simply due to their lifetime warranty. A handfull of other companies offer warranties as well with their tubular mani's.... but FR has been doing it for like 20 years, so they've got this whole production tubular manifold thing down to a science.
FWIW, cracks in your stock manifold are fine. They might leak when the manifold is cold, but as soon as it heats up the cracks seal. I have cracks in mine and i track the **** out of it. No evidence of exhaust leaks from the mani just from inspecting the inside of the heat shield. Usually a leak will show up as carbon deposits on the shield or it'll straight burn through if the leak is bad enough. The inside of my shield is clean.
The problem is the tubular mani's on the X usually warp to **** from heat. Last one I took off had to be pried off the studs. And I installed it, and it went on just fine. So even if it has a warranty, good luck getting it back on after they weld up the crack.
The cracks in your mani may seal now. But you're asking for a problem when one of those crack blows out on track and your car catches on fire...
How long a tubular lasts is totally hit or miss and also dependant on the MFG. For track use, i wouldn't use MAP tubular mani. For street use, its as good as anything else that doesn't come with a lifetime warranty. It's hard to beat full race simply due to their lifetime warranty. A handfull of other companies offer warranties as well with their tubular mani's.... but FR has been doing it for like 20 years, so they've got this whole production tubular manifold thing down to a science.
FWIW, cracks in your stock manifold are fine. They might leak when the manifold is cold, but as soon as it heats up the cracks seal. I have cracks in mine and i track the **** out of it. No evidence of exhaust leaks from the mani just from inspecting the inside of the heat shield. Usually a leak will show up as carbon deposits on the shield or it'll straight burn through if the leak is bad enough. The inside of my shield is clean.
The MAP Mani also has a lifetime warranty and MAP's HQ is a short drive from my house. Proximity is what really makes it the clear choice for me, especially since I was on a time crunch to get a new part. The manifold was literally still warm when I picked it up.
I wouldn't have worried about the cracks if I wasn't bolting a brand new MHI 18K turbo to the other end of it, what little risk there might have been it still just wasn't worth it to me to compromise on the manifold with the amount of money I already had into the repair.
The inside of my shield was the exact opposite of clean, this had little to do with the manifold and much to do with this:
